The paper is devoted to topical issues of qualification of crimes in various forms of complicity in a crime. The research aims at showing the specificity of the various forms of complicity in a crime, a reflection of this specificity in the classification of crimes. The author proceeds from a starting position that any complicity is the activity of a group of people, and the nature of complicity implies participation in the group crime, although the forms of committing a group crime (a crime committed by a number of partners) may be different. The author differentiates between the group the is not a sign of a crime, and the group that is a sign of a crime (constitutive or qualifying), and suggests characteristics of a group of individuals, group of people by prior conspiracy, criminal association (criminal organization). The paper shows the impact of various forms of complicity in a crime on the qualification of crimes, some arguments on the issues of concern are made. The work can be used in law enforcement and scientific activities, in the educational process.